This is an application for continued support of the training program in Pediatric Gastroenterology and Nutrition at the University of California, San Francisco (UCSF). The program has been funded continuously for the past 29 years, and represents the only NIH-supported training facility for this specialty in the Western US. The program objective is to prepare trainees for productive research in pediatric gastroenterology, hepatology and nutrition. The majority of graduates (70%) have proceeded to academic careers. Five years ago, this training grant was restructured to take advantage of the merger between UCSF and Stanford University. With dissolution of the merger, the program is reconfigured in recognition of the current academic environment that requires all trainees to understand molecular and genetic bases of pediatric disorders within the context of new modalities of health care services and value-based research. The program now strives to train highly selected prospects for academic pediatric gastroenterology to function within a team framework, coordinating the efforts of medical scientists with molecular and cell biologists, physiologists, bioengineers, ethnographers, and bioethicists. The current application proposes a more systematic and streamlined approach by (1) training within two primary career paths - Basic Research and Clinical Research - and (2) reducing the number of trainees in the program at any one time. Trainees receive 2-3 years of intensive didactic and practical instruction in basic laboratory or clinical research methods in the context of their own research project. The curriculum combines instruction in developmental aspects of gastrointestinal structure and function with practical experience in laboratory- and/or clinically-based research focused on biomechanisms of growth and differentiation, and disorders which interfere with orderly development. Educational exercises include formal lectures, seminars prepared by trainees, interdisciplinary presentations, and informal discussions of ongoing projects. Trainees attend courses in biostatistics, computer science, principles of bioresearch, and investigational ethics. Each trainee pursues an obligatory research project(s) supervised by experienced preceptors. Requirements are a MD degree and 3 years of residency in clinical pediatrics. Applicants with PhD degrees and defined career goals related to developmental gastroenterology or nutrition are also eligible. The program is administered in the Division of Pediatric Gastroenterology, Hepatology and Nutrition, but utilizes the scientific resources of the entire UCSF campus. Trainees have access to preceptors and laboratories, with associated training resources, in a multidisciplinary environment. Training program leadership is now centralized under the direct supervision of Dr. Melvin B. Heyman, supported by a new K24 grant for mentoring and clinical investigation. Key faculty include two Associate Directors, Core Divisional Faculty and Senior Faculty Mentors with professorial positions at UCSF. Support for 3 trainees per year is requested.